1. Field of the Invention
This invention relates to a system for processing voice information, and, in particular, to a system for registering and/or recognizing voice information.
2. Description of the Prior Art
In voice recognition technology, it is known to produce a plurality of voice patterns by repeating the same sound or word and then to superpose the voice patterns to define a consolidated voice pattern for registration in a voice library. When producing a plurality of voice patterns, the same person can repeat the same sound or word over a predetermined number of times or two or more different persons can produce such voice patters. The reason for superposing a plurality of voice patterns to define a consolidated voice pattern for registration is that such a consolidated voice pattern allows to identify an unknown voice data with an enhanced chance of success because there are usually some differences between voice patterns even if the same person pronounces the same sound or word in succession.
In superposing a plurality of voice patterns for the same sound or word in accordance with the prior art technique, a voice interval for voiced sound is first determined and the superposition is carried our right from the beginning of the voice interval. In this case, if the beginning portion of a voiced word includes a voiced explosive sound or a mono-syllable includes a voiced explosive sound, then it is likely that the explosive sounds of two or more voice patterns do not overly on top of another due, for example, to presence and absence of a bazz bar section and/or differences in time period of such bazz bar section, thereby making it difficult to define a precise consolidated voice pattern for registration. In addition, in a process of recognizing unknown voice information, in accordance with the prior art technique, a voice pattern is produced from the unknown voice information and a voice interval is determined, and, then, matching with registered voice patterns is carried out to identify the unknown voice information. In this case, in accordance with the prior art, the voice pattern of unknown voice information is compared with the registered voice patterns right from the beginning of the voice interval. As mentioned above, this is advantageous because the presence or absence of a bass bar section could lead to a faulty voice recognition.
In addition, it is also well known to reject input voice information if its voice interval is too short because this could present difficulty in carrying out voice recognition processing. If an unknown voice data to be identified is too low in sound level, difficulty is often encountered in identifying the unknown voice data. Thus, it is often desired to reject processing of such an unknown voice data whose sound level is too low.